Synchronizer rings are used as external synchronizer rings, internal synchronizer rings and intermediate rings, wherein in addition a distinction also is made between single-, double- and triple-cone systems. The so-called multiple-cone systems often are used for synchronizing the low gears, as here the speed differences during synchronization are greater than in high gears and larger friction forces therefore are required when accelerating and braking the gearwheels. In an external synchronization the synchronizer ring has a conical outer shell and friction surface, and in an internal synchronization it has a conical inner shell and friction surface.
Synchronizer rings are manufactured for example by forming, i.e., reshaping, a sheet metal, by sintering or forging. The conical friction surface produced is machined in a succeeding working step, in particular coated with an organic or carbon-containing friction lining. Applying a metallic coating by means of galvanic or thermal methods also is possible.
A generic synchronizer ring is known from WO 2010/130442 A2. In this synchronizer ring, which is manufactured by forming a flat material of metal, the conical friction surface is provided with grooves which are produced by axially shifting a tool relative to the friction surface.
It is the object of the invention to further improve the known manufacturing method or the synchronizer ring fabricated therewith.